I focus a lot on the craft of creating conservationally sound oil paintings and best practices for artists in my classroom. This article is for collectors; it’s the other side of the coin, if you will, and how as a collector you can be proactive in understanding what to look
for before investing in a painting, especially if you care about the quality of the work you purchase.
Unfortunately, far too many painters are not properly trained, dismiss the craft for “economic reasons,” or are simply lazy and/or don’t care. As a collector, you have every right to know how a painting has been created and handled prior to purchasing it; in short, learning a bit about the craftsmanship and the care of a work before it ever sees a gallery is important.
Much of this information will be a “given” for sophisticated collectors, but many people simply don’t know and may feel awkward or embarrassed to ask questions. Sometimes it’s a situation of “you don’t know what you don’t know.” I want to change that and educate collectors--both seasoned and new.
I really recommend visiting the artist’s studio. This is where the craftsmanship, care, and preservation of painting begins. Contact the artist and set up an appointment at their studio, not at the gallery. It will tell you a lot, and don’t be shy about asking questions. Make note of the following:
Is the studio kept at a relatively constant temperature and humidity level? This is very important because paint is hydroscopic; it expands and contracts with temperature and humidity fluctuations that can lead to premature cracking, glazing, oxidation, and de-lamination. Wooden stretchers or board can warp and the back of canvas can get moldy in unstable environments. Turning off the heat at night or walking into a studio that is very hot and humid in the summer are not good conditions for oil paintings.
The environment paintings are in should be relatively constant; about 65 to 75 degrees Fahrenheit in the winter and about 70 to 75 degrees in the summer with humidity at approximately 45 to 55 percent. Having ideal museum-quality environmental control in our studios, homes, and offices is both impractical and costly, but the point is that paintings and art supplies should be kept at relatively stable temperature and humidity conditions without major and/or constant changes.
Is the studio reasonably clean and in good repair? This may sound rather Puritan and painting can be a messy process. Entering a dirty, disorganized studio with flickering lights, is a sign that the artist may need to cut corners in other areas such as materials, and they probably are.
Paintings should not be exposed to direct sunlight for extended periods of time. Additionally, unstable microclimates are created close to windows and in windowsills. I know, because one of my paintings was put in the window of a local gallery for about six weeks. A volatile microclimate (complete with condensation on the inside of the windows) and direct sunlight warped the support and I had to remount the painting.
Ask the artist about the materials they use. Make sure they use proper artist-grade materials. If they are using household primer on particleboard, turpentine from the hardware store, or shellac as varnish, these are not good signs. The manufacture and purity standards of artist materials are very different from what is sold in hardware stores and cannot be used for the creation of conservationally sound art.
I know this sounds rather odd, but ask anyway because I’m appalled at what some painters do, even ones who have work in galleries. Ask the painter if they ever “gesso over” a painting and then do a new painting on the canvas. If they say “yes,” politely excuse yourself and move on. This is the single worst and one of the most common practices among some painters, especially those just starting out. Oddly, they see no problem with it, and it makes my head spin.
If paintings are stacked (in a gallery or a studio), make sure that they are vertical, stacked “face to face and back to back,” and not leaning against each other in such a way that will cause divots or impressions in the canvas. Overall having paintings on the floor is not a good practice, but if it must happen make sure you know it's done correctly.
Plastic bubble wrap should never touch the surface of a painting or frame. Not only can bubble wrap leave impressions, it can adhere to the painting. If it is used for shipping, be sure that paper is between the painting and the plastic or bubble wrap. Paintings in storage should be allowed to breathe and never be stored in plastic of any kind.
Paintings that are not on stretchers should not be rolled. (exceptions are giclees, or prints on canvas, and only for shipping). This can very easily lead to cracking. If it must be rolled for shipping or transportation, it should be done as loosely as possible with the painted side on the outside, not the inside. Regardless, it is not a good practice. You want the least amount of movement possible for any oil or acrylic painting.
Make sure the frame is constructed of solid hardwood, not particleboard or composite. “Value” frames from popular craft stores or low-end galleries and framers fall apart easily, look cheap, and don’t provide the rigid support required to prevent movement of the canvas or warping of stretchers or board support. The less movement a painting experiences, the better. Good-quality hardwood frames are not cheap and are reflected in the price of the painting. In my studio, the average cost of a frame for a 16” x 20” painting runs $250 to $400, and the price can easily go higher with true gold leaf. Ask the artist who their framer is and check them out if you have any doubts. Varnish
Oil paintings can take up to one year to dry, especially thick impasto or “palette knife” paintings. Paintings should not be varnished until they are completely dry. If varnished too soon, the oils of the paint will not be able to harden (dry) properly and will result in premature cracking, glazing, etc. Also, as paintings dry, they are very susceptible to temperature, humidity, and light changes which can easily set the stage for premature deterioration; so again, proper storage and a stable environment are very important in the artist’s studio. Varnish is not mandatory, and some artists prefer not to do it because they don’t like the look. There are significant advantages to varnish as it protects the painting from environmental pollutants such as dirt, dust, and general household pollutants such as smoke from the kitchen, pet dander, etc.
Some artists will apply a coat of retouch varnish to a painting to unify the surface if there is not enough time to properly varnish before putting work in a show or gallery. This is a perfectly acceptable practice and far superior to varnishing too soon. Just make sure that a proper coat of varnish applied within a year of purchase.
Again, this is something that an experienced collector would know, but I’m putting it out there for anyone who simply does not have the knowledge. Some artists use their painting mediums such as Liquin or Neo-Megilp in lieu of varnish to even out the surface and give gloss. Run, don’t walk, from anyone who does this.
Cleaning and care of oil paintings at home or in the office
Dust the frame with a soft, dry, clean microfiber or other very soft cloth; do not use household cleaners on the frame.
To clean surface of the painting of dust etc., use a soft artists brush made from sable or badger hair. Be sure it’s 100% natural hair, not synthetic as this can potentially scratch a painting. Avoid feather dusters as they can also scratch the surface.
If your painting is getting quite dirty and dusting does not do the trick, don’t try to clean it at home. Take it to a professional art conservationist who can clean it without damaging the art.
For significant issues such as smoke damage or yellowing varnish, please take your painting to a highly reputable art conservationist who can remove the old varnish and apply a fresh coat. Art conservationists are skilled professionals and are the only people you should trust with any type of maintenance or repairs to your fine art. In my general tri-state region, I recommend Gratz Conservation Studio for oil paintings.
Don’t hang your original art directly over or under air vents, near humidifiers or in an area that receives direct sunlight. Also never put them in bathrooms with a shower (talk about dramatic temperature and humidity changes!) and avoid areas in the kitchen anywhere near the stove.